A man has stunned doctors by coughing up a 6 inch wide blood clot from his lungs in the near-perfect shape of his right bronchial tree. Doctors treating the 36-year-old man were “astonished” when he coughed up the clot The clot could have stayed intact due to a higher than usual concentration of a particular protein, which could have made the blood in his airways unusually rubbery. They said it was possible the man was able to cough it up because of its size, rather than despite it The mysterious, cherry-red cast resembled a piece of coral, and an image of it has gone viral after appearing in The New England Journal of Medicine.